Separately-fired superheater



N \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ml Nov. 13', 1928. I 1,691,698 B. N. BRolDo SEPARATELY FIRED SUPERHEATER Filed June 17; 1924 2 Sheets-Sheet 1 fs '\\\\\\\\\\\\\\\\\\\\\\\\\\\\\j@ lll m1/f INVENTOR BEM/m71# BRO/Do ATTORNEYS Nov. 13, 192s. 1,691,398"

B N. BRolDo SEPARATELY FIRED SUPERHEATER Filed-June 1'7, 1924 2 sheets-sheet 2" INVETOR v Bamm/7W /V. BRO/oo BY 4411, mwww.

Patented Nov. 13, 1928.

` A g items narran stares earner-erstes.

' BnNJAMN n. Bacino, or NE v Yeni/r, Assisi-ton To THE snrnarrnnfrna COM- PANY, or NEW YORK, N. Y., A. conPoRA'rroN or nntawaan.. -v K snrAnATELY-rann surenrrnarnn.

Application mea June 17, 1924. seriai no. 720,476.

rlhis invention relates to superheaters and particularly to separately tired superheaters 'in which the superheater units are heated by the gases from a furnace forming .a part of the superheater installationpas distinguished from thatl type of superheatersv 1n which the elements'are installed in the main boiler of the plant. n Y

rlhe principal object of this invention 1s to provide a new and improved constructiop 1n a device of the character described by means of which the supcrheater units are protected from overheating.'V 'n A Other more specic objects of my invention will be apparent to one skilled in the art to which it appertains' from the following` more detailed description and by reference to the vac'conipanying drawings forming a 'apart Ythereof and wherein an example ofmy inven-r tion is illustrated withoutdeining its limits.

In the drawings: Fig. 1 isa longitudinal vertical section on top thereof. -5

the line 1-1- ofF ig. -2 and Fig. 2 is a trans- Y verse vertical section, the right hand half thereof being taken on the line Y-Y of Fig.

; from the superheating ychamber 11 by Vmeans of a transversely extending re wall12 which terminates a short distance vfrom the top wall 18. of the apparatus to del'ineanv inlet pas-l sage 14 for the furnace gases. y

As shown in Fig. 2, the superheating chamber 11 is provided with a reinforcing-wall 15 vwhich extends longitudinally down theicenremaining front portion vof the superheater ter of the chamber and divides it into two similar halves.'Y 'A pluralityof battle walls 16 and 17 extend transversely across the cham- -ber from'the reinforcing wall 15 to the sidev -walls 18, to provide a tortu'ous' passage 'for E the furnace gases fromthe inlet 1li to the outlet 19 in the rear wall 20 of said chamber.

"lhe 'baffle walls 16' extend 'upwardly from- Vthe floor" of said chamber and terminate a short distance fromtlie top 18 thereof, said Y walls increasing gradually vin height*` from" i the front to the rear of. the chamber; while the baffle walls '17 extend'downwardly from the'top and terminate in the arch shaped ends 21 a short distance'from the floor of said chamber.

Inthe example of thejinvention illustrated I provide a pair of inlet headers 22, 23 located respectively adjacent .tov the front and rear of the chamber 11, an outlet header 24 located adjacent to the center of said chamber, and'avco'nnecting header 25, 25a. between l aresupported by said headersv and' extendV downwardly'into thechamber 11 Yfrom the In ordei` to protect the superheater ele;

the upments from overheating,the units with which -f `the hot gases first come into direct contact are protected` by l interpolatin'g some sup'erheater 1 surfaces ahead of them with which the gases Vdo not come into direct contact, `butwhich Vsurfaces arel e'xposedto the hot gases so'v as to' Vreceive someA of the heat from the-gases. by radiation. The heat exchange between'fthe gases and these interpolatedsurfaces insures cooling of the gasesto a pointv such that 1 and the left hand half on the line X-X of with the next"A .Y

vshown in the l ance with the usualfpractice, thev loops there. l

of extending parallel tofthe lside walls. The

(preferably the first one or two rows) visjarranged outv of the direct path of the gases. This is accomplished by placing tlielirs`t-two rows of vunits 28,' 28a', so that the loops Vex'- `tend transversely ofthe chamber 11` and closely adjacent r"to the baflle'w'all 17.` t -The liotfurnace, gases are deflected froml the rowsof tubes 2,8'b'y` a fire vbrick varchB vwhich is spaced slightly from the bafe wall and extends across,A outside of theltubesn28 approximately opposite ytolthetop ofthefire i' wall; theupper edge'of the archB kpreferably extending a trifle higherl thenthefire j `tends laterally. from each side offthelowerf' wall. A projecting varch-shaped ledge 36 exarch-shaped` bottom edge 21 ofthe-"first baiile wall 17; the forwardly extendingledge/3b -f co-operating with the arch 35*V topreventdii rect Contact of the furnace gaseslwiththe firstv 'the units `2'7" andiswithdrawn in superheated condition through the outlet header 24 the flowof the steain'in this rear pass being substantially counteiitdthe iow of the furnace gases." The flow Vof the steainin the front pass is substantially parallel'to the -gas flow; saturated f steam being yintroduced l into the lunits=28,flowing thence to the units 28a, then tothe intermediate header 25 from which it KVis distributedito Ythe units QSband flows from these last named units to the out-letheader 24.

It will be understood that various changes andmodications of the structure herein dis- ;closedmay-be resorted towithout departing Y frornthevspirit of my invention.

' Aeatingwitlr-saidfurnace and an outlet;I aV

Il claim: i v Y flgfIn a superheater, a furnace-a superrheating.` chamber having aninletjcommuni- ,plurality of superheater tubesY extending within saidv chamberf inthe direct path of the furnace gases, la baille. wall' extending partially acrosssaidxchamber adjacent to said i11let ,aledgev projecting from each side ofthe i ingy alongtheside ofsaidbaffle wal'lwithin l said pockets. 1 l3. In an apparatus of the character de` scribed,.the combinationof afurnace, a heatlbottom of said wall, a deleotingsurfaceextending acrossone side of said wall opposite saidlinlet, saidledge and` delecting suiface forming with said baflle wall a pair of pockets located-oiitofthevflow of the gases from said furnaceVand-a plurality of superheater units extending alongeachside ofsaid baffle wall'withinsaid-pockets.

Iii/an apparatusof the character deseribed, a furnace, a chamber having an inlet: communicating withsaid furnace and an outlet-ya plurality of fluid heating tubesex- .tending withinsaid chamber inthe direct Vpath Aof the furnace'gases, a baffle wall eX- tendingf partially across said chamber adjacent to said inlet, av lurality of ledges pro-1 fjecting from said wa l, said'ledges forming withsaid bafHewall a pair of pockets located loutof the flow` of the gases from'said furnace,

anda plurality offluid heating units extending'chamber in communicationwith saidV furfnacethrough which the furnace gases pass,

and afluidvheating. device in said chamber com'prisingheating. tubes arranged to form a plurality of separate parallel passes, the inajority of said tubes being located inthe direct path of gases from the furnace and the remaining tubes forming a rseparate parallel pass located out of the furnace andqout of the'direct path'of the 'gasesbut exposed to radiation from them, said remaining tubes being heated only by the radiant heat of the furnace and serving to cool said gases before they contact with said majority of tubes, and the gases passing directly from said remaining tubes to said majority of tubes .without-.contacting with any interveninglieat exchange surfaces. i

Li.'In- V an apparatus of tliecharacter described, the combination-of a furnace, a heating chamber in communication with said fur-V nace through which the furnace gases pass, and a fluid heating device coin vrisinga plurality of heating units in sai chamber arranged in two separate passes-connected in parallel, one of said passes being located-in the path of the gases from the furnace in their passage throughthe chamber and the other passbeing located nearer to, but-'out of the furnace and havingA the major portion thereof notwithin the direct path of the gases butexposed' to radiation from'them, said other pass servingto coolt-he furnace gases before they contact with the units of said first-named pass. f Y

5. In an apparatusof .the characterv described,the combination ofl a furnace,a heat-l ing chamberin communication with said furnace throughwhich the furnace gases pass, a plurality off baffle Walls projecting intothe chamber to provide a tortuous passagefor the furnacegases through. the chamber, and a fluid-heating device comprising a pluralityof heating units forming separate passes connectedin parallel, thelmajor portionof said units being arranged'in said tortuous passage in the direct path of the gases, and the remaining vportions forming.V a separate :pass interpolatedin said passage between said major portionand the`furnace,ssaid remaining portions .being arranged o ut of the direct pathrof the gasesbut exposed to radiation froml them,

and serving-t0 cool thefurnace gases before they contact-with-said maj or portion. f

6. In anapparatusl ofV the' character described, a furnace, a chamber in communication with saidrfurnace throughwhich-the furnace gases pass,a' plurality of fluidfheatin tubes mounted within said chamberl at di ferent distances from said furnace and connected to form separate parallel`passes,.those tubes which are locatedin closest'proiimity to the furnace forming a` separate pass andy being arranged out ofthe directpath ofthe furnace gases to receive heattherefroni by radiation and to cool saidgases and the remainingtubes being arranged-,within the direct path of the gases;`

. 7l In an apparatus of the character.' de- Y scribed, a furnace, a chamber having an inlet communicating with said furnace and an outlet; a plurality of balile Walls projecting into said chamber to provide a tortuous passage for the furnace gases through said chamber from said inlet to said outlet, a plurality of fluid heating tubes mounted within said chamber in spaced rows at different distances from said furnace, and connected to form separate parallel passes, the major portion 0f said tubes extending into said passage within the direct path of the furnace gases to be heated thereby by convection, and the remaining tubes being` located nearest to said furnace and forming a separate pass, a plurality of deflecting surfaces adjacent to said remaining tubes to prevent direct contact of the furnace gases therewith, whereby said remaining tubes will absorb heat from said gases substantially by radiation only, andwill also serve to cool said gases before they are permitted to contact with the major portion of said tubes.

8. In anappara-tus of the character described, the combination of a furnace, a heating chamber in communication with said furnace through which the furnace gases pass, a fluid heating device in said chamber comprising a plurality of heating units arranged to form a first pass and a rear pass separate from Vsaid first pass, aplurality of headers arranged to cause the fluid to be heated to flow through said first pass parallel with the gas flow and through said rear pass counter to the gas flow, the units of said rear pass being located Within the direct path of the furnace 3 gases, and the major portion of the units of said first pass nearest to the furnace being located out of the direct pass of the furnace gases but exposed to radiation from them and serving to cool the furnace gases before they sweep over the units of the rear pass.

In testimony whereof I have hereunto set my hand,

BENJAMIN N'. BROIDO. 

